Percentage
Change

Percentages
will appear at some point during your GCSE maths exam. You
will
normally be asked to find a percentage of an amount and then either
increase or decrease the amount by that percentage. You
could also be asked to work out by what percentage an amount has
changed.

Example
Question

a) A secondhand car was
purchased for £8000. After three years the car's value had
decreased by 35%

i) Find 35% of £8000
ii) Find the price of the car after three years.

b) A classic car was bought for £5000. Two years later it was
sold in auction for £6500. What is the percentage increase in
value?

Solution

a)
i) We begin by finding 10% of £8000 by dividing by 10.
So 10% =
£800.